En-masse type drag conveyors are commonly used to convey particulate materials. Most drag conveyors include a continuous chain having a plurality of flights that project outward from the chain. In use, the chain is propelled along the bed of a trough. As the chain moves along the trough, particulate material piled on top of the chain is conveyed or carried along the trough. It is significant that particulate material at the top of the pile is moved in unison with particulate material at the bottom of the pile. Consequently, en-masse type drag conveyors produce little agitation that causes damage to the conveyed particulate matter. Other advantages associated with en-masse type drag conveyors include: low dust levels, low maintenance costs, large capacities and flexible intermediate discharge locations.
A common use for en-masse type drag conveyors is in the grain industry for handling feed and grain. Often, en-masse conveyors work in concert with grain elevators to distribute grain and feed to storage silos. For example, grain elevators are commonly used to move feed and grain vertically from ground level to an elevation above the tops of the storage silos. The silos are typically arranged in rows. En-masse conveyors are used to convey the feed and grain horizontally or at a slight incline/decline from the elevator to the silos. The en-masse conveyors are typically equipped with discharge openings located above the silos. The discharge openings are opened and closed by slide gates. By opening a particular slide gate, feed or grain can be discharged into a selected silo. When the selected silo becomes full, the slide gate is closed such that feed and grain is conveyed past the full silo to the next silo in the row.
Some slide gates are constructed with slide panels or doors that are configured to be flush with the bed of an en-masse conveyor trough. Such a flush configuration is advantageous because it helps reduce drag on the conveyor and limits agitation on the grain or feed. Additionally, a flush configuration eliminates vacant areas in which feed or grain could accumulate and possibly lead to contamination of stored feed or grain.
Several operational problems exist with respect to slide gates having the above described flush configuration. For example, when a slide gate having a flush configuration is opened, the en-mass conveying chain is unsupported as it traverses the discharge opening. As a result, the conveying chain sags within the discharge opening. Such sagging is disadvantageous because the flights of the conveying chain often engage or strike the trough at the downstream end of the discharge opening causing damage to both the chain and trough bed. Additionally, the sagging chain can interfere with the operation of the slide gate, causing the slide gate to jam. Jammed slide gates frequently cause the motors that power the slide gates to burn out.
There currently is a need for a slide gate that addresses the above described problems. There is also a need for a slide gate that is durable and capable of withstanding the harsh environmental conditions typically associated with the handling of particulate material such as grain and feed products. The present invention addresses these needs as well as other needs.